Device and method for demonstrating stagger

ABSTRACT

In one embodiment a device is provided for visually demonstrating stagger. In this embodiment, the device includes first and second tires coaxially mounted on an axle, wherein the first tire has a smaller diameter than the second tire. The device also includes a member configured to be pushed or pulled by a person. The device may be pushed or pulled on a flat surface, such as a paved road. When the device is pushed or pulled in a forward direction, the first and second tires will rotate at the same rotational speed, but because the second tire has a larger diameter than the first tire, the second tire will travel a greater distance than the first tire during each tire rotation. Thus, the device will move in a curved path.

FIELD OF INVENTION

The present application relates to a device for demonstrating stagger.More particularly, the present application relates to a device havingtwo wheels of different diameters to demonstrate stagger.

BACKGROUND

Over the years, professional automobile racing has become increasinglypopular and has garnered many new fans. This increased fan base hascreated a demand for teaching tools that visually demonstrate techniquesused in automobile racing. One such technique is known as “stagger.”

The performance of racing automobiles on banked tracks is often improvedby “staggering” the inside tires as compared with the outside tires.When tires are staggered, such that the inside tires have a smallerdiameter than the outside tires, the outside tires will travel fartherthan the inside tires with each tire revolution, by a distance ofπ*(D_(large)−D_(small)), where D_(large) is the larger diameter of theoutside tires and D_(small) is the smaller diameter of the inside tires.While this difference is nominal over a short distance, over longerdistances the difference in diameters will cause the car to move along acurved path. The tire stagger thus accommodates banked tracks, leadingto higher race car speeds and better handling characteristics.

SUMMARY

One embodiment of the present application is directed to a device andmethod for visually demonstrating stagger. In this embodiment, thedevice includes first and second tires coaxially mounted on an axle,wherein the first tire has a smaller diameter than the second tire,thereby creating a diameter differential. The device also includes amember configured to be pushed or pulled by a person. The device may bepushed or pulled on a surface, such as a paved road or a floor. When thedevice is pushed or pulled in a forward direction, the first and secondtires will rotate at the same rotational speed, but because of thediameter differential, the second tire will travel a greater distancethan the first tire during each tire revolution. Thus, the device willmove in a curved path.

In additional embodiments, the tires of the stagger demonstration devicemay include visual markers to indicate that the tires are rotating atthe same rotational speed. Additionally, the device may be pushed on asurface having a straight line marked thereon. The straight line willprovide a visual reference to demonstrate that when the device is pushedin the direction of the straight line, it will move along a path that iscurved relative to the painted line.

BRIEF DESCRIPTION OF DRAWINGS

In the drawings and description that follows, like elements areidentified with the same reference numerals. The drawings are not toscale and the proportion of certain elements may be exaggerated for thepurpose of illustration.

FIG. 1 is a simplified front view of one embodiment of a device 100 forvisually demonstrating stagger.

FIG. 2 is a perspective view of one embodiment of a system 200 forvisually demonstrating stagger.

FIG. 3 is a flow chart illustrating one embodiment of a method 300 forvisually demonstrating stagger.

DETAILED DESCRIPTION

The following includes definitions of selected terms employed herein.The definitions include various examples and/or forms of components thatfall within the scope of a term and that may be used for implementation.The examples are not intended to be limiting. Both singular and pluralforms of terms may be within the definitions.

“Axial” or “axially,” as used herein, refer to a direction that isparallel to the axis of rotation of a tire.

“Circumferential” and “circumferentially,” as used herein, refer to adirection extending along the perimeter of the surface of the annulartread perpendicular to the axial direction.

The present application is directed to a device and method for visuallydemonstrating stagger. The device is configured such that when it ispushed or pulled in a forward direction, it will move along a curvedpath.

FIG. 1 illustrates a simplified front view of one embodiment of astagger demonstrating device 100. In this embodiment,, first and secondtires 110,120 are coaxially mounted on wheels (not shown) which aresubsequently mounted on an axle 130. The first tire 110 has a firstdiameter D₁ and the second tire 120 has a second diameter D₂ that isgreater than the first diameter D₁. To achieve this differential betweenthe diameters, a user can employ tires having different dimensions.Alternatively, the user can employ tires have the same dimensions andcreate a diameter differential by deflating the first tire relative tothe second tire.

In the present embodiment, the first and second tires 110,120 areconfigured to rotate at the same rotational speed, because they arecoaxially mounted on the same axle 130. Because the second tire 120 hasa greater diameter D₂ then the first diameter D₁, the second tire willtravel farther than the first tire during each tire revolution. Morespecifically, during a single revolution, the first tire 110 will travela distance equal to its circumference C₁, which is equal to π*D₁, andthe second tire 120 will travel a distance equal to its circumferenceC₂, which is equal to π*D₂. Therefore, during each rotation, the secondtire will travel an additional distance that is equal to C₂−C₁, orπ*(D₂−D₁).

In one embodiment, the second diameter D₂ is at least 0.25 inchesgreater than the first diameter D₁. Therefore, the second tire 120travels at least 0.257 inches (or at least approximately 0.785 inches)farther than the first tire 110 during each revolution of the tires110,120. In another embodiment, the first diameter D₁ is approximately26.84 inches and the second diameter D₂ is approximately 27.27 inches.Therefore, the second diameter D₂ is approximately 0.43 inches greaterthan the first diameter D₁ and the second tire 120 travels approximately0.43π inches (or approximately 1.35 inches) farther than the first tire110 during each revolution of the tires 110,120. On the Indianapolis 500racetrack, or a similarly dimensioned racetrack, the second tire 120would travel approximately 21 feet farther in each turn than the firsttire 110.

With continued reference to FIG. 1, the device 100 also includes amember configured to allow a person to push or pull the device 100. Inthe illustrated embodiment, the member is a T-shaped handle 140. Inalternative embodiments (not shown), the member can be a handle of anyshape, including, without limitation, an L-shaped handle, a straighthandle, or a steering wheel shaped handle. In an additional alternativeembodiment (not shown), the member is a harness. In the presentembodiment, the handle 140 is directly connected to the axle 130. In analternative embodiment (not shown), the handle 140 is indirectlyconnected to the axle 130.

In one embodiment, each of the first and second tires 110,120 includesat least one visual marker 150 a,b to help indicate the rotation of thetires. In the illustrated embodiment, the first tire 110 has a firstvisual marker 150 a and the second tire 120 has a second visual marker150 b at a location that corresponds circumferentially with the locationof the first visual marker 150 a on the first tire, such that both thefirst and second visual markers 150 a,b reach top dead center at thesame time during rotation of the axle 130.

In alternative embodiments, each tire 110,120 includes a plurality ofvisual markers. The visual markers may be aligned or off-set withrespect to each other. Furthermore, the visual markers may havedifferent colors. The visual markers may be painted on the tire or theymay be adhesively applied.

FIG. 2 illustrates one embodiment of a system 200 for visuallydemonstrating stagger. In this embodiment, the system 200 includes astagger demonstrating device 100 as explained above. The system furtherincludes a surface 210 on which the device 100 may be moved. Examples ofsurfaces include, without limitation, a flat section of a paved surfaceor a floor.

In the illustrated embodiment, the surface 210 is marked with a straightline 220 that may serve as a visual reference. The straight line 220 maybe painted on the surface 210 or it may be applied by an adhesive. In analternative embodiment (not shown), a straight object or a series ofobjects may be used to indicate a straight path. In an alternativeembodiment (not shown), the surface 210 is marked with a line thatapproximates the curved path 230 that the device 100 will follow.

With continued reference to FIG. 2, the device 100 is placed adjacentthe straight line 220 such that the first and second tires 110,120 areapproximately parallel to the straight line 220. A user then pushes thedevice 100 in a forward direction that corresponds to the direction ofthe straight line 220. As the device 100 is moved forward, it travelsalong a curved path 230 relative to the straight line 220. In oneembodiment (not shown), tire 110 or tire 120 or both are configured toapply an indicator on the surface 210 to mark the path of travel 230.Examples of indicators that may be applied include, without limitation,paint or water.

FIG. 3 is a flow chart diagram of one exemplary method 300 for visuallydemonstrating stagger. Initially, a demonstrator provides a staggerdemonstration device (step 310). The stagger demonstration deviceincludes a member for pushing or pulling the device and two coaxiallymounted wheels having different diameters. The demonstrator nextprovides a surface (step 320). In one embodiment, the surface is markedwith a straight line. In an alternative embodiment, the surface ismarked with a curved line that approximates the path the staggerdemonstration device will follow. If the surface is marked with a line,the demonstrator may optionally align the device with the marked line.

The demonstrator then pushes the device in a forward direction (step330). The difference between the diameters of the wheels will cause thedevice to move along a curved path. The demonstrator may move the devicea short distance to show that the stagger may not be visible over shortdistances. The demonstrator may then continue to move the device over alonger distance to provide a visual indication of the curved path thedevice follows due to stagger.

While the present application has been illustrated by the description ofembodiments thereof, and while the embodiments have been described insome detail, it is not the intention of the applicants to restrict or inany way limit the scope of the appended claims to such detail.Additional advantages and modifications will readily appear to thoseskilled in the art. Therefore, the application, in its broader aspects,is not limited to the specific details, the representative apparatus, onthe illustrative embodiments shown and described. Accordingly,departures may be made from such details without departing from thespirit or scope of the applicant's general inventive concept.

1. A device for visually demonstrating stagger, the device comprising: afirst and second tire, wherein the first tire has a smaller diameterthan the second tire; an axle connected to the first and second tires,such that the first and second tires are coaxial; and a member connectedto the axle and configured to be pushed or pulled by a person.
 2. Thedevice of claim 1, wherein the first and second tires each include atleast one visual marker at corresponding circumferential locations, suchthat during rotation of the tires, the visual marker of each tirereaches top dead center at the same time.
 3. The device of claim 2,wherein the visual marker is a painted stripe.
 4. The device of claim 1,wherein the diameter of the first tire is at least .25 inches less thanthe diameter of the second tire.
 5. The device of claim 1, wherein thediameter of the first tire is about .43 inches less than the diameter ofthe second tire.
 6. The device of claim 1, wherein the member configuredto be pushed or pulled by a person is a handle.
 7. A system fordemonstrating stagger, the system comprising: a surface; and a deviceconfigured to be pushed or pulled by a person, wherein the deviceincludes: an axle; a first tire having a first diameter, configured tobe axially mounted on the axle; a second tire having a second diameterthat is larger than the first diameter, the second tire configured to beaxially mounted on the axle, opposite the first tire; and a memberconnected to the axle and configured to be pushed or pulled by a person.8. The system of claim 7, wherein the first and second tires each haveat least one visual marker at corresponding circumferential locations,such that when the first and second tires are rotated on the axle, thevisual markers reach top dead center at the same time.
 9. The system ofclaim 7, wherein the surface is a section of paved road having astraight line marked thereon.
 10. The system of claim 9, wherein thedevice is configured to be pushed or pulled on the section of pavedroad, such that if the device is pushed or pulled in the direction ofthe straight line, the difference between the first and second diameterscause the device to move along a curved path.
 11. The system of claim 7,wherein the second diameter is at least .25 inches larger than the firstdiameter.
 12. The system of claim 7, wherein the second diameter isabout .43 inches larger than the first diameter.
 13. The system of claim7, wherein the member configured to be pushed or pulled by a person is ahandle.
 14. A method for visually demonstrating stagger, the methodcomprising the steps of: providing a surface; providing a device havingfirst and second co-axially mounted tires, wherein the second tire has alarger dimension than the first tire; and pushing the device on thesurface in a forward direction, wherein the larger dimension of thefirst tire causes the device to move along a curved path.
 15. The methodof claim 14, further comprising a step of marking each of the first andsecond tires with at least one visual marker at corresponding locations.16. The method of claim 14, wherein the device includes a handleconfigured to be pushed or pulled by a person.
 17. The method of claim14, wherein a diameter of the second tire is at least .25 inches greaterthan a diameter of the second tire.
 18. The method of claim 14, whereina diameter of the second tire is about .43 inches greater than adiameter of the second tire.
 19. The method of claim 14, furthercomprising a step of marking the surface with a straight line, such thatwhen the device is pushed, it will travel along a path that is curvedrelative to the marked line.